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Mr_Roboto

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For you precision rifle guys I have a dumb question. I'm loading 243 win with 100gr Sierra BTHPs. The COAL the book says is 2.65 which I'm thinking is just silly since that's not even close to mag length. Testing rifling engagement I got 2.802 with this bullet for full engagement and am going back to 2.795 for testing on some of my ammo with the rest starting at 2.740. Any reason I shouldn't do this? I believe I'm going the right route here.

The higher end of these loads is supposedly compressed, although I may be able to avoid that with the longer loads. If I don't have to worry about loose bullets due to lack of neck tension or accuracy loss or something similar I'd rather have the stick out.

I may end up having to get some bullets that are a slightly longer shape/ogive to make some of the distance up. Just gotta try and keep it below about 2.83 for mag reasons. I'm obviously not trying to shoot 115s here but some 105s or 107s would be nice. Any recommendations? Platform is an LR-308 with pmags. 1:8 twist barrel.
 
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Did some casting, made about 2Kish bullets. Some 9mm and some for the revolvers.

bullets.jpg
 
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Mr_Roboto

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Just got some more bullets for the 243, punching some numbers around in Strelok. These are standard 100gr vs 105gr 243 win bullets. I put the velocity at the same initial velocity but chances are the 100gr would have 20-30FPS more for any given powder. Still really interesting. Notice how even at 100 yards the 105gr bullets have significantly less velocity drop. IMO this covers perhaps one of the biggest weaknesses of 243 win compared to some contemporary calibers (6mm creed comes to mind) is that the bullet selection leaves something to be desired if you're wanting to match shoot. I'm going to end up loading some of both of these up with Ramshot Magpro and IMR 7828 and seeing what they do.

Bullet weight grains: 105.0;
Bullet speed f/s: 3013.0;
Ballistic coefficient (G1): 0.517;
Zero Distance yards: 109.0;
Scope height inches: 2.0;
Vert. click MOA: 0.25;
Hor. click MOA: 0.25;
Altitude feet: 328.0;
Temperature °F: 59.0;
Pressure inHg: 29.53;
Wind speed mph: 0.0;
Wind direction degrees: 90.0;

Distance yards;Bullet speed f/s;Vert. correction MOA;Hor. correction MOA;
100.0;2833.0;-0.03;0.0;
200.0;2659.8;1.10;0.0;
300.0;2493.4;3.05;0.0;
400.0;2334.0;5.36;0.0;
500.0;2180.8;7.96;0.0;
600.0;2034.4;10.86;0.0;
700.0;1894.0;14.08;0.0;
800.0;1760.2;17.66;0.0;

Bullet weight grains: 100.0;
Bullet speed f/s: 3013.0;
Ballistic coefficient (G1): 0.403;
Zero Distance yards: 109.0;
Scope height inches: 2.0;
Vert. click MOA: 0.25;
Hor. click MOA: 0.25;
Altitude feet: 328.0;
Temperature °F: 59.0;
Pressure inHg: 29.53;
Wind speed mph: 0.0;
Wind direction degrees: 90.0;

Distance yards;Bullet speed f/s;Vert. correction MOA;Hor. correction MOA;
100.0;2783.5;-0.03;0.0;
200.0;2565.0;1.18;0.0;
300.0;2357.6;3.27;0.0;
400.0;2161.4;5.81;0.0;
500.0;1975.4;8.76;0.0;
600.0;1800.2;12.14;0.0;
700.0;1634.8;16.03;0.0;
800.0;1479.7;20.51;0.0;
 
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Mr_Roboto

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Welp, I preordered for a Lee Ammo Processing Plant. I size enough bullets that I decided to see if it was worth it or not to do. I'll probably put a video up on YouTube for it at some point. It's a neat concept in that it will work upside down as well as right side up and feeds the cases through automagically when doing operations like primer swagging, bullet sizing or case resizing. I've got a bunch of military crimped 5.56 to play with and a ton of 9mm/.357 bullets to size.

https://leeprecision.com/app-automatic-processing-press/

I also got a set of autoprime shell holders and a 450 Bushmaster die set. I have a bunch of 300gr .458 bullets I'm going to size to .452 and some H4198 powder I'm going to throw in them. Here's to hoping they feed right the Ruger bolt actions I've seen reports of them being finicky about bullet shape but I'm in an AR platform which I hope makes the difference.
 

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